Despite an overwhelming need for effective CNS therapeutics, little progress has been made. Improving CNS drug discovery efforts is an urgent goal, as an estimated 1.5 billion people suffer from a CNS-related disease or disorder worldwide. We believe that a major roadblock toward more effective CNS therapeutics is the lack of neuron-based probe discovery platforms cable of supporting HTS-level screening. It seems logical that CNS disease targets should be assayed in neurons instead of cell-lines, though the use of neurons in HTS screening campaigns is uncommon. We argue that development of a flexible and scalable neuron-based assay development platform that is compatible with HTS would facilitate probe development, while also perhaps spurring drug discovery efforts aimed at treating a variety of brain diseases. One of the significant barriers preventing R01-driven investigators from interacting with screening centers is the inability of these centers to miniaturize and scale-up neuron-based assays. We have developed an innovative approach for migrating neuron-based benchtop assays to an HTS-ready platform in order to make HTS more accessible to neurobiologists interested in probe discovery. The Neuroscience Department at Scripps Florida has engaged the Screening Center and the Lead ID group at TSRI in collaborative efforts to overcome this barrier and we have identified ways to alter current procedures so that neuron-based benchtop assays can be miniaturized and automated to produce turnkey assays capable of supporting biological and chemical screens with tens-of-thousands of molecules. We propose that the neuroscience field would benefit tremendously from a system that enabled a migratory route for bench-top neuron-based assays to be miniaturized and then scaled, leading to their use in HTS probe discovery campaigns. Importantly, the system that we have developed will also provide investigators with a toolset to develop novel assays for neuron-based HTS. Our proposal details plans to develop novel reagents, instrumentation and workflows that will demonstrate that a bench-top assay developed in primary neurons can be migrated to an HTS-compatible assay. As a proof of principle, we will migrate a bench-top synaptogenesis assay to this HTS-enabled system. We then propose to take this HTS-ready, neuron-based assay through a screen of ~25,000 compounds. Successful achievement of a screen of this magnitude in primary neurons would demonstrate that primary neurons can be used as a common platform for drug/probe discovery and that our approach could serve as a general assay development system for neuron-based HTS. Thus, the outcome of this project is expected to provide researchers and Screening Centers with an assay development platform capable of supporting HTS-level screens in a neuronal environment. Thus, funding this proposal will result in novel probes to regulate synaptogenesis, but will also generally serve the Neuroscience community as a whole by providing an assay development platform that can be used by anyone interested in scaling up bench-top assays for HTS campaigns.